Im not a musician. I never thought great musical ability had anything to do with great songs though. Take Depeche Modes 'Just Cant Get Enough' for example. A classic but Im sure even I could play that one. Same goes for a lot of punk songs.
I think songwriting is more important than musical ability.
I think all the members of U2 are excellent musicians. Musicianship is so much more than being able to play tricky riffs or being able to play incredibly fast and complicated stuff. Musicianship is (or should be) more about being able to move people with your playing, being able to bring out emotions from your listener and being able to convey your emotions through your playing. In that sense U2 are excellent.
Since when were U2 not good musicians? Edge is one of the best guitarists out there, and I'm yet to hear a rhythm section as powerful as Larry and Adam. That's all.
...songs that i can play on guitar= bad, dumb, easy, musically-suspect songs
because if you have any guitar skill, then you can pretty much dismiss just about the entire rock-n-roll movement of the last 40 years as musically inept
i will follow and pride are both pretty damn simple and pretty damn ingenious
you dont have to play your guitar with a weed wacker or try to invent a new chord to be a great musician